| 摘要 |
<p>980,194. Percussive drills. PHILLIPS DRILL CO. Jan. 2, 1962, No. 167/62. Heading B4C. A chuck 10 for a hollow self-drilling anchor shell 12 has an axial passage 11 for receiving the shell, a transverse passage 26 for a shell ejector tool, and a transverse passage 19 having connections 20, 21 to a source of vacuum 24 for removal of drilling debris. The part 18 of the chuck is releasably connected to an electric hammer 23. During drilling the chuck may be intermittently rotated by a handle 25, and the passage 26 is closed by a rotatable cover 32.</p> |
